Your lack of experience of the English education system is one of the issues here.
How long has your daughter been in the English education system?
I'm going to try and explain how things work. Forgive me if I'm being too detailed or telling you things you already know.
Your daughter should have arrived in secondary school in year 7 aged 11. She should have started studying English, maths and other subjects then.
In English, she will have already studied some Shakespeare and other novels and poetry. This would have been preparing her for the gcse course. She will also have done some creative writing, which is preparation for English language.
If she joined the school in year 7, you should have attended a parents information evening, which would have explained all about the school, subjects, homework and other expectations.
At the end of year 9, beginning of year 10, you should have had another parents information evening, explaining about gcse choices and the requirements for each subject.
On the school website, there should be a section about the curriculum and each subject, explaining the content and exams.
There may possibly be a homework timetable on the student/ parent portal. This will show you how much time should be spent on each subject per night/week. There should also be a record of any homework set. It's a good idea to check regularly on the parent portal.
You should also have an evening once a year where you can discuss your daughters progress in each subject, and areas for improvement. Plus regular school reports.
The most commonly used texts for English literature are: A Christmas carol; An Inspector Calls; Macbeth; an anthology of poetry - 15 poems; plus unseen poetry - this means she should be able to write about a poem which she has not read before.
Make sure that you attend any parents evenings next year and discuss your daughters progress and what she needs to do.